Gamma-cyclohexylcrotonaldehyde



3,031,507 'y-CYCLOHEXYLCROTONALDEHYDE Claire Ortoli and Rene Revcrchon,Lyon, France, assignors to Societe des Usines Chimiqnes Rhone-Roulette,Paris, France, a French corporation No Drawing. Filed Oct. 24, 1958,der. No. 760,318 Claims priority, application France Oct. 31, 1957 1Claim. (Cl. 260-598) This invention relates to'y-cyclohexylcrotonaldehyde.

It is an object of the present invention to provide a new compound whichwhen incorporated in perfume compositions comprising also otherodoriferous compounds will enhance or supplement their eifect.

The present invention comprises, as a new compound,'y-cyclohexylcrotonaldehyde, which has been found to have particularproperties by virtue of which it can be advantageously applied in theerfumery industry. This aldehyde has the following formula:

CHg-CH: C 2 \CHCH2CH=CHCHO CHz-OE; and the following characteristics:

B.P. (8 mm.) 104-105 C. d20=0.931 n =l.4875,

Its semicarbazone melts at 195 C.

The invention also comprises perfume compositions comprising a pluralityof odoriferous compounds of which one is cyclohexylcrotonaldehyde;preferably the -cyclohexylcrotonaldehyde is present in a minorproportion only, e.g. less than 5% and especially less than 2%, of thewhole composition. The new aldehyde has a very powerful, rich, cuminicsmell, and in these small proportions it enhances and supplements theeffect of the other odoriferous components of the composition.

In one method of making the new aldehyde, cyclohexylaldehyde iscondensed with acetaldehyde, preferably in the presence of a basiccatalyst, and preferably also using a substantial excess of theacetaldehyde. In another, cyclohexylaldehyde is condensed with a vinylether, preferably with the aid of a Friedel-Crafts catalyst, and theresulting 1:3-dioxan derivative split by means of an acid into thecyclohexylcrotonaldehyde, cyclohexylacetaldehyde, and alcohol.

' The invention is illustrated by the following examples.

Example I A mixture of 63 g. of cyclohexylacetaldehyde, 150 g. ofacetaldehyde and 100 cc. ethyl alcohol is run, in 30 minutes and at 200., into a solution of 2 g. of sodium hydroxide in 100 cc. of ethanol.The reaction mixture is mm'ntained at 20 C. for 7 hours, whereafter itis allowed to stand for 14 hours at room temperature. The product isacidified with acetic acid, diluted with 1000 cc. of water, andextracted with cyclohexane, and the cyclohexane layer is washed withwater. The solvent is driven off and the product is distilled. There areobtained, in addition to 40 g. of cyclohexylacetaldehyde, 14.4 g. of afraction boiling at 116122 C. under 10 mm. Hg and containing 50% of'y-cyclohexylcrotonaldehyde. On rectification of this fraction, the purecompound is obtained.

Example 11 3 g. of ether and 0.4 g. of boron fluoride etherate areintroduced into a 500 cc. flask filled with nitrogen. A mixture of 126g. of cyclohexylacetaldehyde and 36 g. of

3,031,507 Patented Apr. 24, 1902 vinyl ethyl ether is run into the flaskover a period of 1 hour with agitation. Reaction commences and thetemperature rises. The temperature is maintained at 55-60 C. until allthe mixture has been run in. The resulting mixture is then stirred for afurther hour, whereafter the boron fluoride is destroyed by the additionof 10 cc. of a 10% sodium acetate solution, and the contents of theflask allowed to separate into two layers. After decanta tion of theaqueous layer, the organic layer is heated under reflux with g. offormic acid for 4 hours and then cooled. 100 cc. of cyclohexane areadded, and the mixture is washed with water until neutral and distilledunder nitrogen. There are obtained 34.7 g. of a fraction boiling at -115'C. under 8 mm. Hg and containing 90% of y-cyclohexylcrotonaldehyde. Onrectification of this fraction, the pure compound is obtaiued.

Example 111 A lilac perfume has the following composition. (The partsare by weight.) 1

Parts y-Cyclohexylcrotonaldehyde 5 Anisaldehyde 10 Isoeugenol 10 Beuzylacetate 10 Styrax balsam 10 Bergamot oil 2O Linalool 30 Heliotropine 100Cinnamyl alcohol Hydroxycitronellal Phenylethyl alcohol Terpineol 380Example IV A rose perfume has the following composition. (The parts areby weight.)

As a compound, y-cyclohexylcrotonaldehyde.

References Cited in the file of this patent FOREIGN PATENTS GreatBritain Mar. 7, 1951 OTHER REFERENCES Venus-Danilova: ChemicalAbstracts, vol. 29 (1935), page 2152.

Fieser et al.: Organic Chemistry, 3rd ed. (1956), page 208.

